Hatches, particularly hatches for boats, are fairly well known devices that allow ingress and egress into and out of enclosed areas, e.g., boat cabins, and/or allow light to enter an enclosed area. Deck hatches are available in many sizes, from small ventilation hatches to larger hatches used as emergency exit points. A ventilation hatch might be as small as 12×12 inches, where as a typical large hatch intended for persons and objects to pass through might be 20×20 inches. Hatches, thus, generally comprise assemblies that allow entry, exiting and closure, generally comprise a cover, a base, hinge means connecting the cover and the base, and a gasket means between the cover and the base to ensure a water-tight seal. Hatches may be installed on boat hulls and decks. Standard production boats typically have decks fabricated of fiberglass. The outer surface is often mirror finished, while the underside of the deck is typically raw and unfinished.
Boat builders economically install a deck hatch by further including a trim ring. The trim ring is usually molded from thermo-formed plastic or formed by bending aluminum angle extrusions. The trim ring engages between a spigot on the hatch base which extends inside a cutout in the boat deck, for example, and the portion of the deck which comprises the edge of the deck opening for the hatch. The slip fit of the trim ring to the deck hatch is critical and highly visible. A spigot, or vertical flange, on both the trim ring and the hatch base are desirable to allow for overlap for enabling a slip fit. More importantly, the trim ring and hatch base must be able to variably overlap, as deck thicknesses vary. Typical spigot lengths are 1 inch to 1⅛ inches. The overlapping spigot on the trim ring can be varied to suit, from commonly ½ inch to 4 inches or more.
Heretofore, boat hatches, and more particularly, hatch bases were fabricated exclusively of aluminum or plastic, due to the shape to which they must conform. Since aluminum is not a very stiff/rigid metal, i.e. flexural properties, it can readily undergo the required bends to conform to the hatch shape without experiencing unacceptable deformation. Since hatches are highly visible components on boats, however, it is of the utmost importance that they do not appear warped, crooked, or otherwise misshaped.
In contradistinction to aluminum boat hatches, hatches fabricated from stainless steel have not been used in volume production boat building, and rarely in boat building at all, because of the rigid properties of stainless steel, and concomitant higher manufacturing costs. The rigid properties of stainless steel inhibit bending of the workpiece to the required radii without significant visual distortion to the frame caused by stress forces generated during the bending process. Often times, however, stainless steel would be preferable over aluminum or plastic because it will not readily rust, corrode, warp, or deform, once in place. Additionally, stainless steel does not require the usual protective coatings or treatments, as is the case with aluminum.
Stainless steel hatch bases may be fabricated, but they normally require considerably more time to manufacture and install, which translates into substantially higher costs. Heretofore, one method for fabricating stainless steel hatches has been by traditional bending methods. However, such earlier methods resulted in excessive visual distortion in the hatch base having a traditional cross-section, a spigot was not included as an integral part of the hatch base. Consequently, a trim ring could not be used because there was no spigot with which to engage. Instead, the boat builder would custom design, craft, and install a trim ring substitute, which drastically raised production time, and therefore, costs making them economically unattractive. Accordingly, stainless steel for use in marine hatches has not been considered an acceptable material for production boat building, and has been reserved primarily for use by specialty boat builders.
To date, there have been no stainless steel hatch bases available which included spigots. Historically, hatch bases are all similar to an angle shape, generally having horizontal flanges about 1¼ inches wide, and vertical spigots of 1 inch or more. This traditional shape, when made from thin walled stainless steel, results in too much flaring, or distortion, of the flange and/or spigot after bending to be acceptable for use in the marine industry. A distorted hatch frame is not aesthetically attractive and also results in an engagement with the trim ring which is not uniform or constant.
What is needed, then, is a stainless steel hatch which includes inter-alia a base design which is economically attractive for most commercial production boat building.